Introduction: A surgeon’s level of mental workload is elevated in suturing, particularly during the learning phase. Training decreases the workload of the surgeon as movements become automatic and require less mental resources. To objectively quantify mental workload during learning, we developed a simple bench-top measurement tool to assess the spared mental resources that are available for surgeons during suturing. We hypothesize that surgeons who are confident in making sutures would have better mental workload reserves to allow accurate detection of distractive visual signals, compared to surgeons who are still learning laparoscopic suturing skills.

Methods: Suturing tasks were performed on a bench-top training box. Participants performed as many sutures as possible in 6 minutes while an adjacent monitor, placed 15 degrees off axis, randomly displayed 30 true visual signals. Each true signal appeared for 1 second. Ninety false signals also appeared randomly. Participants were required to identify the true signals while suturing. Participants included 12 junior residents (novices) and 9 fellows and attending surgeons (experts). Suturing was evaluated using the FLS scoring system. The secondary (visual detection) task was evaluated by calculating the rate of missing true signals and detecting false signals.

Conclusion: Practice develops automaticity, which reduces the mental workload and allows surgeons to have more mental resources for responding to environmental factors. The ability to quantify mental resources has implications for surgical training (measuring expertise) and for measuring situation awareness ability during real surgeries.